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arXiv · 1203.1491

Reentrant topological phases in Mn-doped HgTe quantum wells

W. Beugeling·C. X. Liu·E. G. Novik·L. W. Molenkamp·C. Morais Smith
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Abstract

Quantum wells of HgTe doped with Mn display the quantum anomalous Hall effect due to the magnetic moments of the Mn ions. In the presence of a magnetic field, these magnetic moments induce an effective nonlinear Zeeman effect, causing a nonmonotonic bending of the Landau levels. As a consequence, the quantized (spin) Hall conductivity exhibits a reentrant behavior as one increases the magnetic field. Here, we will discuss the appearance of different types of reentrant behavior as a function of Mn concentration, well thickness, and temperature, based on the qualitative form of the Landau-level spectrum in an effective four-band model.

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W. Beugeling, C. X. Liu, E. G. Novik, L. W. Molenkamp, C. Morais Smith. 2012-03-07. Reentrant topological phases in Mn-doped HgTe quantum wells. https://doi.org/10.1103/physrevb.85.195304

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